Last time we talked about Keys and Imprints. There are other ways that triangles and squares may present on crystals. We'll discuss those here, namely Growth Interference and Record Keepers.

GROWTH INTERFERENCE

Indentations and markings similar to Imprints and Keys also occur but they fall into a different category. Some of these triangular and square-shaped impressions are caused by what is called Growth Interference. Growth Interference happens when another mineral grows during the development of the crystal and then subsequently disappears.